917H hydro: leaks, check valves, etc.

[mikeg75]

Hello again. I posted earlier concerning my 917, which I have owned for about 4 months. It has been a drought-influenced summer: I mowed very little. I still haven't solved the "only running on choke" problem. I tightened the clamps I could see, and replaced the fuel filter. I wonder if it could be the fuel pump? I think I will also check the manifold, gaskets, fuel tank screen as others suggested. I replaced the deck drive belt, and started looking at the tranny area. I noticed some oil leakage on the axle area, and wasn't sure what this was from. I thought maybe the leakage was from the transmission, so I took off the trans fluid fill cap, and couldn't see the oil. The manual mentioned the proper oil level checking procedure was to push the free-wheel lock down, and raise the relief valve. When I pushed the free-wheel lock down, it didn't do anything - the check valve stems seem to be frozen so they stick up about 1/4" above the valve bodies. The relief valve appeared to be two threaded fittings with a stem like a popup turkey timer - do you have to pull this inner stem up with a pliers? I can't see any way to grip it. I don't know if it is necessary to have "unfrozen" check valves, or to pull up on the relief valve. Can I just add oil, up to the top of the tube? What type of oil (manual says AC 821) should I use? I have no Idea what the prev. owner used. Also, is there fluid for the final drive or other area, which may be leaking on the axles? Thanks in advance.

[RayS]

On the relief valve just pull up on the stem and cock it side ways, it should stay open for you until you are done. The check valves can be freed up by removing them from the tractor and working them back and forth with a oil (WD40 or something simular). You may have to tap on the stems with a hammer lightly to get them moving. If it were mine I would drain the fluid and replace the filter as well. I use ATF type F in mine but you can use Dextron and Simplicty Multi-visocity oil in it as well. Raising the relief valve will release pressure from inside the case and help the oil go in alot easier.

[mikeg75]

Thanks Ray, that is helpful. Are the check valves only necessary for free-wheeling? If so, I may make freeing them a winter project. If I fill without raising the relief valve, will it result in a different fluid level than if I filled properly? (don't want to overfill). What type of filter is appropriate? 1650954? 1709322? I thought I saw someone mention a NAPA filter, I don't know which number. I have a new filter for my JD 317 hydro, I don't know if it is the same or not. Also, the manual mentioned "final drive fluid level" - is this the same thing as we have been talking about? Thanks much. You guys have made this a lot easier for me.

[PatRarick]

I think you are confusing the check valves. I could be wrong, but I can't see where any of my manuals say anything about pushing down the free wheel lock when adding or changing fluid. The check valves on the hydro unit should be sticking up about 1/4" for operation, and be pushed down to flush with the valve bodies for free wheeling. They don't pull up. As long as your tractor will move, they are up as far as they'll go. The check valve for adding or refilling the fluid is in the transmission case itself. It's on the left side of the transaxle, when viewed from the rear. Just in front and a little above the axle. A 3/8" pipe nipple, about 1 1/2" long with an elbow pointing upwards. The check valve is screwed into the top of the elbow, much like a pipe plug. It looks like a little nail head on this valve that is spring loaded to close. You need to pull up on this little head to let the air escape from the transmission case when adding or changing the fluid. I never mess with trying to hold the valve open. I usually clean off the valve, unscrew it from the elbow, add fluid, then replace the valve when the transaxle is filled. Pat

[mikeg75]

Thanks Pat- that is very helpful. I don't think I can pull up on the relief valve, unless I use a knife to pry it up (haven't tried yet). I like what you suggest, just simply unscrewing it from the elbow. I think it looked like it needed a 7/16 or 1/2" wrench to remove it. Thanks again

[2burning]

NAPA filter for the side of transmission mounted ones is 1335, or 51335 WIX number. Crosses to the 1709322 filter. The 1650954 number is a tall filter for the 700 series AC or 7000 serires Simp., which is on a remote mount ahead of the transmission. Oh, and their is just one resivoir for the final drive and hydo, it's all-in-one. So you just have to drain in one location and fill in one location.

[mikeg75]

Hey, thanks. I called carquest, they carry a 85335 filter (I think made by WIX), which is 3.670 OD, 2.483" long. This 1335 also crosses to an AC PF2210. Does the length make much difference?

[stevenj]

As I recall from discussions of past, not all brands of hydraulic filters are created equal. Some of the brands do not have the correct micron rating and flat out won't work properly. I'm pretty sure Wix, Baldwin, NAPA, and of course Simplicity filters were recommended. I'd just use the Simplicity recommended filter and not worry about it. Check out this post that I found by using the Search the Forums function. http://simpletractors.com/club2/topic.asp?ARCHIVE=true&TOPIC_ID=19507&SearchTerms=hydro,wix

[mikeg75]

I checked the existing filter tonight. It is a number 1650954, and it is side mounted on the transmission. I picked up a napa gold 1335 filter, it is a bit shorter, but maybe I will give it a whirl....<edit>: The existing 1650954 is just a bit shy of the back wheel - I don't know if this is the correct filter for this tractor, or not. The 1650954 cross referenced to a WIX 51307 filter, which was the closest length among 3 models. I don't know if anyone has tried this filter or not. Also, I have an unused JD AM39653 filter for a 317 hydro, which appears to be the same size as the simplicity. Whew. I'm going in circles. The reason for avoiding simplicity filters is the Allis dealer will have to order the filter, and I would like to mow this weekend. (6" grass). Any thoughts? You all have been a great help.

[RayS]

The side mounted filter is shorter than the one that is in the middle of tractor on older models, just behind the BGB. The NAPA 1335 is what I have on one of mine.

[mikeg75]

stevenj- I read the thread you attached to your message - it is exactly what I need - I am convinced now that the filter was supposed to be the short model, as it says in the 7100 series parts manual. I will go with the 1335. Thanks again. I wish all forums were this good....

[2burning]

Hey mikeg75, I have read out here from those much more knowledgeable than myself that there is a 'short', 'medium' and 'long' Simplicity filter. They long one is for the remote mount 7000 series or 700 serires AC. Then they went to the short filter for the side mount 7100 series and 900 series AC. At some point in the early 90's? or so they found that the short filter was noisy, so they started using a medium filter on the side mount to help the hydro be quieter. So on a side mount filter the prefered one would be a medium, but a short will work but may be noisier if the machine is a newer vintage machine. I would say if the correct, quality filter fits and it's not in the way of the tires, chains, or rear pto then go for it!